Research On Gas Outburst Prediction Indexs About No.3 Coal Seam In West Area Of Sihe Coal Mine

China is one of the nations that have grievous coal and gas outburst problems,gas outburst prediction is the key technology of gas prevention and treatment,moreover,the core content of outburst prediction is the sensitivity of indexs.In order to study the sensitive indexs and critical values of the NO.3 coal seam in Sihe mine,this paper utilized the geological structure control theory and geological evolution history,summarized the coalbed gas geology law and gas outburst characteristics of NO.3 coal seam in Sihe mining area initially.Based on the gas outburst integrative theory,follow-up inspection data,physical meaning of prediction indexs and gas outburst law of the NO.3 coal seam,researched the gas outburst prediction indexs'sensitivity qualitatively,and then,analyzed the indexs'sensitivity by grey relational analysis method quantitatively.Combined with the results of qualitative and quantitative analysis,established the sensitive gas outburst prediction indexs which were residual gas content W and gas desorption index K1 about the NO.3 coal seam in west area of Sihe mine.Through selecting different kinds of disturbed coal samples,established experiments about gas desorption dynamic characteristics and residual gas content,and ascertained the sensitive indexs'critical values initially;Based on the connotation of the critical range and critical values,set up the principle of ascertaining critical values via"three rate"statistical method,ascertained the sensitive indexs'critical range and values finally,the critical value of W is 10m3/t and the critical value of K1 is 0.75 mL/(g.min1/2).